%0 Journal Article %A Horton, J. D. %T Sets with No Empty Convex 7-Gons %J Canadian mathematical bulletin %D 1983 %P 482-484 %V 26 %N 4 %U http://geodesic.mathdoc.fr/articles/10.4153/CMB-1983-077-8/ %R 10.4153/CMB-1983-077-8 %F 10_4153_CMB_1983_077_8